Science
Our drug candidate EL 924 designed to Address Unmet Needs in the Global Obesity and Insulin Resistance Epidemic
The Challenge
The Incretin-Based Weight-Loss Paradox. The most effective therapy can only work if patients continue to take it.
Exceptionally effective on individual level but limited effectiveness to address obesity epidemic on population level
GLP-1/GIP therapies have transformed obesity treatment, producing remarkable weight loss in many individual patients. Yet their population-level impact remains constrained by long-term persistence, tolerability, lean-mass loss, cost, access, and the need for chronic treatment.
This creates an important paradox: exceptional efficacy in clinical trials does not necessarily translate into durable effectiveness in the real world. In the pivotal SURMOUNT-1 trial, only 4.3–7.1% of tirzepatide-treated participants discontinued therapy because of adverse events. Yet in a large real-world study of GLP-1–based therapies, approximately 65% of patients with overweight or obesity without diabetes discontinued treatment within one year, increasing to approximately 84% by two years (Jastreboff et al., 2022; Rodriguez et al., 2025).
Next-generation therapies have further increased weight-loss efficacy, but have not eliminated tolerability and treatment-discontinuation challenges. In the 2026 Phase 3 TRIUMPH-1 trial, the GIP/GLP-1/glucagon triple agonist retatrutide produced up to 28.3% mean weight loss at 80 weeks, while adverse-event–related discontinuation increased with dose, reaching 11.3% at the 12-mg dose—numerically higher than the 4.3–7.1% observed with tirzepatide in the pivotal SURMOUNT-1 trial.
Increasing efficacy alone, therefore, may not solve the long-term treatment challenge.
Addressing the obesity epidemic will require complementary therapies that advance not only efficacy, but also long-term tolerability, persistence, scalability, affordability, and suitability for chronic use.
Elaphron is developing a differentiated approach designed around these needs.
References
Jastreboff AM et al. N Engl J Med. 2022;387:205–216. SURMOUNT-1: tirzepatide produced up to 20.9% mean weight loss; adverse-event–related discontinuation was 4.3–7.1%.
Rodriguez PJ et al. JAMA Netw Open. 2025;8:e2457349. Real-world cohort of 125,474 adults: among patients without type 2 diabetes, 64.8% discontinued GLP-1–based therapy within one year and 84.4% within two years.
TRIUMPH-1 Phase 3, 2026. Retatrutide produced up to 28.3% mean weight loss at 80 weeks; adverse-event–related discontinuation increased with dose, reaching 11.3% at 12 mg.
35%
100M+
Our approach and biologic basis for EL 924:
Mimicking the Profound Metabolic Benefits of Bariatric Surgery with a Simple Oral Therapy:
A Novel Approach to Obesity Beyond Appetite Suppression
Metabolic surgeries such as gastric bypass produce profound and rapid benefits in insulin resistance, diabetes, broader metabolic health and obesity. The depth and speed of these effects exceed what has been achieved with available medical therapies.
A growing body of evidence suggests that many of these benefits are driven not simply by calorie restriction or weight loss, but by changes in food flow, intestinal nutrient sensing, bile acid signaling, and broader food-driven gut metabolic signaling. These mechanisms may help lower the metabolically defended body-weight set point. This concept is supported by human clinical observations that gastric bypass can induce diabetes remission even in non-obese patients, and by ileal transposition models, where surgical driven portion restriction (stomach size reduction) has no role.
At Elaphron, our approach is designed to mimic key aspects of this biology without surgery. EL-924 is a non-absorbed, locally acting oral therapy designed to reshape how the gut senses and responds to food, with the goal of rebalancing gut-derived metabolic signaling involved in body-weight regulation, insulin sensitivity, and broader metabolic health — similar to pathways engaged by metabolic surgery.
The Intestine as a Master Regulator of Metabolic Health and Obesity
The intestine is not only an organ of digestion and absorption. It is a powerful and highly active metabolic, immune, neural, and hormonal signaling organ that helps regulate body weight, insulin sensitivity, glucose metabolism, lipid metabolism, inflammation, feeding behavior, brain function, adipose and muscle signaling, and broader metabolic and hormonal health.
Through nutrition-driven signaling pathways
Current incretin therapies based on gut-derived hormones such as GLP-1 and GIP validate the exceptional power of intestinal hormonal signaling, but they represent only a small part of a much larger nutrition-driven gut regulatory network activated by gastric bypass.
This broader system includes multiple coordinated pathways:
Gut-derived hormonal signaling: GLP-1, GIP, PYY, ghrelin, CCK, oxyntomodulin, glicentin, neurotensin, serotonin, motilin, somatostatin, secretin, and pancreatic polypeptide.
Bile acid and metabolic signaling: bile acid circulation, FXR/TGR5 pathways, and downstream FGF19/FGF21-related signaling.
Neural signaling: vagal signaling, enteric nervous system activity, and nutrient-responsive gut-brain communication.
Nutrient sensing and epithelial biology: driven by food diversion – nutrient transporters, enteroendocrine cell activity, epithelial barrier function, intestinal ion-channel function, and local mucosal signaling.
Immune and inflammatory signaling: gut immune-cell activity, epithelial-immune interactions, and local inflammatory regulation.
Microbiome-related signaling: microbiota-derived metabolites and microbiome-mediated effects on gut and systemic metabolism.
Systemic endocrine and metabolic networks influenced by the gut: insulin, glucagon, IGF-1, adiponectin, leptin, myokines, skeletal-muscle and adipose endocrine signaling, and ceramide/ceramidase-related metabolic pathways.
Together, these pathways form a complex food-responsive regulatory network that may help explain why metabolic surgery can produce effects on weight, insulin resistance, diabetes, and cardiometabolic health that exceed what is typically achieved by targeting GLP-1/GIP signaling alone.
Modern dietary patterns may chronically disrupt this system. Highly processed, energy-dense diets can alter nutrient exposure in the proximal intestine and contribute to durable changes in intestinal epithelial cell composition, behavior, nutrient sensing, and signaling. Over time, these changes may distort how the gut responds to food, leading to dysfunctional gut-derived signaling that contributes to insulin resistance, obesity, type 2 diabetes, and broader metabolic dysfunction.
By modifying these hormonal and metabolic signals through controlled nutrient interaction, receptor modulation, ion-channel modulation, and bile acid signaling effectively mimicking gastric bypass, it may be possible to treat obesity and insulin resistance at an upstream biological control point, rather than relying solely on appetite suppression or downstream metabolic intervention.
EL 924 - Mechanism of Action, Preclinical Efficacy, Early Human Signals for Safety, Tolerability, Efficacy, Lean Mass Preservation, and Rapid Insulin-Resistance Reversal
Mechanism of Action
EL-924 is a non-absorbable, locally acting carbohydrate-derived metallo-heteropolymer incorporating bioactive coordination complexes selected for their activity, favorable safety profiles, and poor systemic absorption.
After oral administration, EL-924 forms a transient intestinal coating that self-eliminates within hours. The polymer and its associated bioactive complexes create a local interface designed to modulate intestinal receptors, transporters, ion channels, and nutrient- and bile acid–sensing pathways.
By reshaping how the gut responds to food-derived signals, EL-924 is designed to reproduce selected metabolic effects associated with gastric bypass through a non-surgical, gut-localized approach.
Preclinical Obesity Efficacy
In obese mouse models (C57BL6), EL-924 produced approximately 7% weight loss per week, reaching approximately 14% weight loss by two weeks, with strong reproducibility across experiments. This magnitude is directionally comparable to historical semaglutide/Ozempic effects reported in obese mouse models.
A key differentiation factor is that EL-924’s weight-loss effect was observed without reduced food intake, altered feeding behavior, signs of feeding discomfort, diarrhea, bloating, or other observed toxicity signals. This supports a mechanism distinct from appetite suppression and suggests favorable GI tolerability in preclinical testing.
In crossover animal experiments, EL-924 demonstrated highly reproducible effects. Although partial weight regain occurred rapidly after treatment discontinuation, the weight-loss benefit persisted for approximately three times the active weight loss treatment duration. By comparison, historical GLP-1 animal data suggest return to baseline weight occurs over approximately 1.5 times the active weight loss treatment duration, supporting the possibility of a differentiated durability profile.
Early Human Observations with EL-924
Limited, non-pivotal, real-world observations N2
Limited, non-pivotal N2 real-world human observations with EL-924 (N2) have shown encouraging early signals, including exceptional tolerability, apparent safety with prolonged use, significant weight loss with preservation of lean mass, and highly favorable body-composition changes.
EL-924 was associated with approximately 30% body-fat reduction within 17 weeks, while lean mass was preserved. This is potentially differentiated from appetite suppressive – therapies, where approximately 25% of total weight lost may come from lean mass, meaning larger total weight loss and longer treatment duration may be required to achieve comparable favorable body-composition changes.
EL-924 also showed a rapid and substantial insulin-resistance signal. Insulin-resistance indices improved by approximately 3-fold within 3 weeks and up to 4.8-fold within 17 weeks, moving from a prediabetic insulin-resistance range toward exceptionally high insulin sensitivity profile. Importantly, the initial and larger improvement occurred before significant weight loss, supporting a potential weight-loss-independent metabolic mechanism.
The magnitude and speed of this insulin-resistance signal appear directionally closer to the rapid metabolic effects observed after bariatric/metabolic surgery than to the slower, more modest, and largely weight-loss-associated insulin-sensitivity improvements typically reported with GLP-1/GIP-based therapies.
These early real-world observational signals are encouraging, but they are limited, non-pivotal, and require confirmation in controlled clinical studies.
EL-924: Key Advantages and Differentiation from Incretin-Based Therapies
This creates potential for:
Potential Role in the Obesity Treatment Ecosystem
A key differentiator for EL-924 is that preclinical weight loss was observed without reduced food intake, altered feeding behavior, signs of feeding discomfort, or significant stool changes. Early human observations also suggest good tolerability and rapid improvement in insulin resistance before substantial weight loss, supporting a mechanism distinct from appetite suppression.
In preclinical models, EL-924 produced significant weight loss ,while preserving food intake.
Next-generation incretin therapies may achieve greater maximal weight loss in animal models, but tolerability, lean-mass preservation, long-term persistence, and dependence on chronic appetite suppression remain important considerations.
EL-924 is being developed as a differentiated option for patients in whom metabolic benefit, tolerability, preservation of lean mass and physical function, and maintenance of normal eating behavior may be particularly important.
Its distinct mechanism may also create opportunities for complementary use with incretin-based therapies.
Sarcopenic obesity, where preservation of lean mass is clinically important
Stand-alone use in patients who cannot tolerate incretin-based therapies and when GLP1 level weight loss is enough
Stand-alone use in patients seeking weight loss without severe restriction of eating behavior, loss of food enjoyment, lean mass loss, or performance limitations
Combination therapy with GLP-1/GIP or other incretin-based agents for patients who require greater-than-GLP1-level weight loss
Lower-dose incretin combinations to improve tolerability when continuation of incretin-based therapy is desirable
Weight-loss maintenance after discontinuation of appetite-suppressive therapy, potentially allowing patients to return to more normal eating patterns with reduced risk of weight regain
PRN Use for prevention or mitigation of episodic weight gain in non-obese or weight-stable individuals during periods of increased food intake, such as holidays, travel, or vacation
Potential benefit beyond obesity: Approximately 20% of normal-weight adults may have a metabolically unhealthy phenotype—sometimes described as metabolically unhealthy normal weight or “metabolically obese normal weight”—characterized by insulin resistance and metabolic dyslipidemia and associated with substantially increased cardiometabolic risk. EL-924 has shown rapid improvements in insulin resistance and metabolic dyslipidemia before substantial weight loss, suggesting potential utility in this underserved population.
Lean Mass Preservation
Lean-Mass Preservation
Early observations with EL-924 suggest preservation of lean mass during weight loss, potentially reflecting its distinct, non-appetite-suppressive mechanism.
Gastric bypass produces substantial lean-mass loss despite favorable changes in metabolic and anabolic signaling, likely influenced by the profound caloric restriction accompanying early postoperative weight loss. In contrast, ileal transposition alters intestinal nutrient and hormonal signaling without gastric restriction; in animal studies, it reduced adiposity while largely preserving lean mass.
Similarly, EL-924 produced weight loss in preclinical studies without reduced food intake, potentially avoiding calorie-deficit signals that contribute to lean-mass loss.
The mechanism remains under investigation. If confirmed clinically, lean-mass preservation could represent an important differentiator for EL-924.
References
Nuijten MAH et al. Obes Rev. 2022;23:e13370. Lean- and fat-free-mass changes following bariatric surgery.
Somogyi E et al. Physiol Behav. 2020;219:112844. Ileal transposition, energy balance and body composition in rats.
EL-924: Potentially Best-in-Class Nutritional Signal–Modifying Technology
Our approach—modulating gut-derived nutrient signaling with an oral, polymer-based technology—is part of a rapidly emerging field with growing scientific and commercial interest.
Current approaches face several development challenges, including achieving meaningful biological activity while maintaining gastrointestinal tolerability and a practical oral dose.
EL-924 was designed to address these challenges.
In preclinical studies, EL-924 demonstrated substantial weight-loss activity without observed reductions in food intake, disruption of feeding behavior, significant stool changes, or gastrointestinal adverse effects in the studies conducted to date.
Importantly, comparative preclinical data suggest that EL-924 may require up to sevenfold less material to achieve a meaningful biological effect than other polymer-based nutrient-signaling approaches. This higher activity per amount of material may enable a lower pill burden and more practical oral dosing.
Together, these findings suggest the potential for a differentiated profile combining efficacy, low material requirements, gastrointestinal tolerability, and preservation of normal feeding and bowel behavior. Clinical studies are required to confirm these findings.
Limitations of Metabolic Surgery–Mimetic Approaches and Ways to Address Them
Variable response: Gut nutritional-signaling reprogramming may not work for every patient. Bariatric surgery, EndoBarrier, and epithelial resurfacing literature suggest meaningful responses in a Majority of patients (potentially 50-90%) but not for all, obesity is heterogeneous, with both non-responders and hyper-responders expected similar to GLP/GIP data.
GI tolerability: Nutrient-diversion approaches can increase delivery of undigested nutrients to lower regions of the gut, which may trigger bloating, nausea, diarrhea, and lead to SIBO. Elaphron has worked to address this through targeted modifications to EL-924’s polymer design.
Absorption monitoring: Potential effects on vitamin, micronutrient, and drug absorption are valid concerns. No meaningful vitamin or micronutrient absorption issues have been observed in our prolonged-use human observational data, but this will remain an important area for clinical monitoring.
Manageability: Bariatric surgery experience suggests nutrient or medication-absorption changes can often be managed through routine monitoring, supplementation, and medication-dose adjustment when needed similar to GLP/GIP therapies that may require supplements
Broader Platform Validation
Together, EL-156 and EL-787 support the broader platform concept: by tuning local intestinal coating, epithelial interaction, and GI signaling, the same core technology can generate differentiated therapies across metabolic, inflammatory, functional, and secretory GI diseases.
